1. Field of the Invention
The present invention relates, in general, to a process for producing ozone-containing sterilizing water and apparatus therefor, in particular, to a continuous process for producing ozone-containing sterilizing water used in cleaning/sterilizing various foods or devices in a simple and highly efficient manner and apparatus therefor.
2. Description of the Prior Art
Generally, ozone (O3) has been used in sterilization, bleaching, and oxidization because ozone has strong oxidizing power. Particularly, ozone-containing sterilizing water has been extensively used in food processing or medical fields because no toxic components remain after the cleansing or sterilization therewith.
Ozone-containing sterilizing water is conventionally produced by two processes: a bubble type process, in which ozone gas is added into raw water in the form of bubbles through an ozonizer connected with a vessel holding raw water; and an injector type process, in which ozone gas is added into raw water with the use of a pressure difference resulting from a flow velocity change of raw water passing through a venturi-tube.
However, such bubble type process has problems in that ozone gas added into raw water is not, for the most part, dissolved in raw water, but released from the water surface to the atmosphere, so that low levels of the ozone gas remaining in raw water can perform sterilization only at a low efficiency. What is worse, the released ozone gas is hazardous to humans and causes air pollution.
In the case of the injector type process, since ozone gas is added into raw water with the use of a pressure difference resulting from a flow velocity change of raw water passing through a venturi-tube, solubility of ozone in raw water can be increased but a little to sterilize only the raw water itself. In other words, the ozone concentration prepared by the injector type process is too low to endow raw water with a bactericidal activity.
According to the prior arts, therefore, bacteria in raw water can be killed, but it is impossible to produce ozone-containing sterilizing water with a bactericidal activity, which can sterilize something else other than raw water.
Meanwhile, efforts have been made to overcome the problems and to produce ozone-containing sterilizing water by taking advantage of the solubility increase of ozone gas with the increasing of pressure. For example, the solubility of ozone in raw water is increased by applying pressure into a compression tank into which raw water and zone gas are provided.
However, this method suffers from the problem of being unable to produce ozone-containing water in a continuous type process. That is, ozone-containing sterilizing water can be produced in the quantity as large as the volume of the compression tank in a batch type process, and the production process must be repeated from the beginning stage in order to give ozone-containing sterilizing water in the same amount. The use of huge compression tanks for making a detour around the volume limitation has problems in that the facility and production cost is increased and large amounts of ozone gas should be added into raw water, producing the pollution of the air. Also, the ozone-containing water, although being produced in a sufficient quantity, is disadvantageous in that the ozone gas dissolved therein may be decomposed or released to the atmosphere during storage, thereby reducing a sterilizing efficiency of the ozone-containing water.
Accordingly, there remains a need for providing an apparatus and method that overcome the above problems and can produce ozone-containing sterilizing water continuously and with high efficiency.
Therefore, it is an object of the present invention to alleviate said problems of the prior arts and to supply an effective, continuous process for producing ozone-containing sterilizing water.
Furthermore, it is another object of the present invention to supply a simple, improved apparatus used in the continuous process for producing ozone-containing sterilizing water.
According to the present invention, there is supplied a process for continuously producing ozone-containing sterilizing water, comprising the steps of: introducing raw water and ozone gas, together, into a compression tank to produce a bubble phase mixture, in which raw water is moved at a faster speed at a predetermined passage to induce a pressure drop, and ozone gas is drawn into the compression tank by the pressure drop; charging bubble phase mixture into any one of compartments of the compression tank, and pressurizing the mixture in the charged compartment to give ozone-containing sterilizing water, in which the compartments are sealably separated by a movable partition within the compression tank; moving the partition to reduce the volume of filled compartment to discharge the ozone-containing sterilizing water while the other compartment is expanded in volume through being charged with the bubble phase mixture; and repeating the above steps.
According to an embodiment of the present invention, raw water and ozone gas are introduced through an injector having a structure with a narrowed cross section therein, raw water is moved at a faster speed at the narrowed cross section to induce a pressure drop, leading to the drawing of the ozone gas into the injector.
Furthermore, the bubble phase mixture is maintained in the compartment for 15 sec to 5 min under a pressure of 15 to 40 kg/cm2, and preferably for 0.5 to 1 min under a pressure of 20 to 30 kg/cm2.
Optionally, the compression tank comprises two compartments divided by a partition, and the partition of the compression tank is a sealably reciprocating piston member. The partition of the compression tank may also be a flexible resilient diaphragm placed in the middle of the compression tank.
According to the present invention, there is supplied an apparatus for continuously producing ozone-containing sterilizing water, comprising a pump for transferring a bubble phase mixture of raw water and ozone gas; and a compression tank, divided into a plurality of compartments, for pressurizing the bubble phase mixture to produce ozone-containing sterilzing water, the plural compartments, in turns, receiving, pressurizing, and discharging the bubble phase mixture.
According to another embodiment of the present invention, the apparatus further comprises an injector for introducing raw water and ozone gas into the compression tank. The injector has a structure with a narrowed cross section therein, such that the raw water is moved at a faster speed at the narrowed cross section to induce a pressure drop, leading to the drawing of the ozone gas into the injector.
Optionally, the compression tank forms a hollow cylinder, comprising a piston member sealably reciprocating within the hollow cylinder; and, a guide bar, extended from the piston to the outside of the compression tank through a hole established in one side of the hollow cylinder, for guiding the motion of the reciprocating piston member, whereby the hollow cylinder is divided into a first compartment and a second compartment by the piston member and the compartments vary in volume according to the motion of the piston member.
The piston member is provided with a plurality of sealing rings at its outer circumference to sealably separate the first and the second compartment from each other so as to prevent the leakage of a fluid pressure exerted on either of the compartments into the other compartment, and the hole is provided with a plurality of sealing rings at its wall to prevent the leakage of a fluid pressure of the compartment to the outside therethrough during the reciprocating motion of the guide bar.
Furthermore, the guide bar allows the piston member to be at a regular position in the hollow cylinder, and is marked on its one side with degrees so that the position of the piston member can be easily seen from outside.
Also, each of the two compartments has an inlet for introducing a bubble phase mixture of raw water and ozone gas, and an outlet for discharging pressurized ozone-containing sterilizing water, wherein a pair of an inlet and an outlet are formed in each of the upper verge and lower verge of the cylinder, respectively.
Optionally, plural compartments are defined by a flexible resilient diaphragm placed in the middle of the compression tank, consisting of a first compartment and a second compartment. The flexible resilient diaphragm is operated in such a way that the flexible resilient diaphragm is expanded toward the second compartment by increasing the pressure of the first compartment to a predetermined value and maintaining the pressure for a predetermined period of time to discharge a fluid from the second compartment, and toward the first compartment by increasing the pressure of the second compartment to a predetermined value and maintaining the pressure for a predetermined period of time to discharge a fluid from the first compartment.
According to the present invention, there is supplied an apparatus for continuously producing ozone-containing sterilizing water, comprising a pump for transferring a bubble phase mixture of raw water and ozone gas; and a cylindrical compression tank, divided into a plurality of compartments by a donut-type piston member having a hole at the center, for pressurizing the bubble phase mixture to produce ozone-containing sterilizing water. The piston member is provided with a plurality of sealing rings at its circumference and at the inner circumference of the hole to sealably separate the plural compartments from each other so as to prevent the leakage of a fluid pressure exerted on either of the compartments into the other compartment, and moving, along a guide bar, in such a reciprocating manner within the compression tank as to pressurize the bubble phase mixture in the plural compartments, in turn. The guide bar extends from one end side of the compression tank to the other side through the hole of the piston member to support the reciprocating motion of the piston member.
According to another embodiment of the present invention, the apparatus further comprises an injector for introducing raw water and ozone gas into the compression tank. The injector has a structure with a narrowed cross section such that the raw water is moved at a faster speed at the narrowed cross section to induce a pressure drop, leading to the drawing of the ozone gas into the injector.
The cylinder further comprises a piston proximity sensor for monitoring the position of the piston within the cylindrical compression tank and determining whether the piston is normally operated or not.
In addition, each of the two compartments has an inlet for introducing a bubble phase mixture of raw water and ozone gas and an outlet for discharging pressurized ozone-containing sterilizing water, wherein a pair of an inlet and an outlet are formed in each of the upper verge and lower verge of the cylinder, respectively.
Furthermore, a backflow prevention check valve is provided just before the inlets for introducing raw water and ozone gas into the injector, each, to prevent the raw water and ozone gas from flowing backward by a back pressure of the pump.
In the present invention, there is supplied an apparatus for continuously producing ozone-containing sterilizing water, comprising an injector for mixing raw water with ozone gas to give a bubble phase mixture of raw water and ozone gas, in which the injector has a structure with a narrowed cross section therein, and the raw water is moved at a faster speed at the narrowed cross section to induce a pressure drop, leading to the drawing of the ozone gas into the injector; a pump for transferring a bubble phase mixture of the raw water and ozone gas; and a compressions tank, formed into a hollow cylinder, for pressurizing the bubble phase mixture to produce ozone-containing sterilizing water, wherein
the compression tank comprises a piston member sealably reciprocating within the hollow cylinder; and a guide bar, extended from the piston to the outside of the compression tank through a hole established in one side of the hollow cylinder, for guiding the motion of the reciprocating piston member, whereby the hollow cylinder is divided into a first compartment and a second compartment by the piston member and the compartments vary in volume, in turn, to pressurize the bubble phase mixture according to the reciprocating motion of the piston member.
According to another embodiment of the present invention, the cylinder further comprises a piston proximity sensor for monitoring the position of the piston within the cylindrical compression tank and determining whether the piston is normally operated or not.
Additionally, a backflow prevention check valve is provided just before the inlets for introducing raw water and ozone gas into the injector, respectively, to prevent the raw water and ozone gas from flowing backward by a back pressure of the pump.
According to another embodiment of the present invention, the first and the second compartment are individually provided with an inlet for introducing the bubble phase mixture of ozone gas a raw water thereinto and an outlet for discharging the pressurized ozone-containing sterilizing water therefrom, wherein a pair of an inlet and an outlet are formed in each of the upper verge and lower verge of the cylinder, respectively. The apparatus further comprises a storage tank for storing the ozone-containing sterilizing water, provided with an off-gas filter for venting the gas generated during the storage of the ozone-containing sterilizing in the storage tank; a first conduit, provided with a first solenoid valve, for connecting each outlet with said storage tank; and a second conduit, provided with a second solenoid valve, for connecting each outlet with a drainage pipe.
The first and second solenoid valve function in such a way that, during the trial run of said apparatus, the second solenoid valve is opened with closing of said first solenoid valve so as to drain unpressurized raw water from the compression tank and, during the steady operation of said apparatus, the first solenoid valve is opened with closing of the second solenoid valve so as to discharge ozone-containing sterilizing water into the storage tank.
In the present invention, there is supplied an apparatus for continuously producing ozone-containing sterilizing water, comprising an injector for mixing raw water with ozone gas to give a bubble phase mixture of raw water and ozone gas, in which the injector has a structure with a narrowed cross section therein, and the raw water is moved at a faster speed at the narrowed cross section to induce a pressure drop, leading to the drawing of the ozone gas into the injector; a pump for transferring a bubble phase mixture of the raw water and ozone gas; and a compression tank, formed into a hollow cylinder, for pressurizing the bubble phase mixture to produce ozone-containing sterilizing water, wherein
the hollow cylinder is divided into a first and a second compartment by a flexible resilient diaphragm placed in the middle of the compression tank, the flexible resilient diaphragm is operated in such a way that the flexible resilient diaphragm is expanded toward the second compartment by increasing the pressure of the first compartment to a predetermined value and maintaining the pressure for a predetermined period of time to discharge a fluid from the second compartment, and toward the first compartment by increasing the pressure of the second compartment to a predetermined value and maintaining the pressure for a predetermined period of time to discharge a fluid from the first compartment.
According to another embodiment of the present invention, the first land the second compartment are individually provided with an inlet for introducing the bubble phase mixture of ozone gas and raw water thereinto and an outlet for discharging the pressurized ozone-containing sterilizing water therefrom, wherein a pair of an inlet and an outlet are formed in each of the upper verge and lower verge of the cylinder, respectively. The apparatus further comprises a storage tank for storing the ozone-containing sterilizing water, provided with an off-gas filter for venting the gas generated during the storage of the ozone-containing sterilizing in the storage tank; a first conduit, provided with a first solenoid valve, for connecting each outlet with said storage tank; and a second conduit, provided with a second solenoid valve, for connecting each outlet with a drainage pipe.
The first and second solenoid valves function in such a way that, during the trial run of said apparatus, the second solenoid valve is opened with closing of said first solenoid valve so as to drain unpressurized raw water from the compression tank and, during the steady operation of the apparatus, the first solenoid valve is opened with closing of the second solenoid valve so as to discharge ozone-containing sterilizing water into the storage tank.